There is a book called “Curation Nation” that explains the growing use of curation as a business model for web-based business models. The premise is that aggregation sites (that present you with everything in an order that is based on a web-crawling and page-rank kind of algorithm) are losing their popularity because of search engine optimizers and too much junk out there.
Instead, we are using our social networks or experts to filter the cream from the crop. We find people who we trust in particular areas (movie critics or friends who share our taste in movies; fashion icons or friends who share our taste in clothes; etc) and then listen to their recommendations. So the growth of reputation management systems and recommendation systems are becoming more critical than search algorithms and search engine optimization strategies.